The incredible true story of a high-ranking intelligence officer, Robert Hanssen, who betrays US secrets to foreign powers, and the young FBI agent tasked with capturing him. Based on witness testimony and official case records that remained secret until now, it's about betrayal from within, by a traitor believed to be a friend. In the secret world of counter intelligence, one fear looms larger than all others. A threat from within by a traitor you believe is a friend. Suspicion points to a key figure in western intelligence, trading secrets worth billions of dollars, causing damage on a global scale. Enter the world of espionage and discover the incredible story of Robert Hansen, double agent. In the heart of Washington DC there's a spy among the very people charged with protecting the nation - the FBI. When a double agent secretly accuses one of the top names in US intelligence a desperate race begins. How can the traitor be netted before he betrays more precious secrets? Can the shocking claims be probed without alerting a man who himself knows every trick of the spying trade? The agonising choices facing US spymasters in the of fall 2000 sound like a thriller plotline – but they are fact. There was no manual for a mission like this. In the secret world of counter-intelligence it was a nightmare scenario. The spy catchers had a spy in their midst. With exclusive first-time access to Eric O'Neill, the FBI agent tasked with discovering the truth, this film at last reveals the untold story of the West's worst ever spying disaster involving turncoat FBI boss Robert Hanssen. His treachery led to torture and death for several agents, advanced the threat of nuclear war, and cost the US billions of dollars. The most sensitive spy-on-spy mission ever mounted was handed to 27-year-old rookie Eric O'Neill who, with only four years experience at the FBI, had to draw out the 25-year veteran spymaster and catch him off guard. Using O'Neill's testimony and a stylishly craft